Method for installing new felt seal on inner primary cover.(2020)

I’m new to this site and to Commando’s but not new to British and other bikes.

I’m sure this question has been asked before – just need to learn how to search.

I’m ready to install the inner primary cover on my Commando. I am confident in my shim determination. I have a new felt seal for the transmission shaft to cover interface.

What, if any is the technique to install? Before I drill the spot welds, separate the plates and pop-rivet back together with the new seal – figured I’s ask.

Thank You

Installing the felt seal is challenging i tried all the hacks on this site for installing it, all without success...
i used new plates, but drilling out the spot welds to re use the existing plates is fine.
Once separated align the two plates drill out as required and insert 3mm machine screws and self locking nuts.. or plain nuts and Loctite together once assembled with the inner chain case and new seal installed first
I used 6 screws on mine
i also applied a layer of Wellseal on the plates before assembly, nip the screws up evenly
Job done

I struggled with that seal when doing the inner casing first time last year. I made some small progress after squashing the new, oil soaked felt between two plates in a vice overnight, then working a little bit in at a time using right angled needle nose pliers and small flat blade screwdriver. Never did get it perfectly seated but went ahead and declared victory. Its not a critical piece as it does not make much of a seal even when new and perfect.

BTW, be sure to use locktite on the three inner cover fixing bolts. The metal fold locks are not sufficient to prevent bolt unwinding (don't ask how I know this fact).

There is an OldBrits torque guide for Commando that also has good tips like not putting 70ft-lbs on the clutch nut b/c it distorts the little clutch C clip beneath. They recommend around 40 ft-lbs and locktite.

put oil on the felt.
sandwich it between two pieces of plywood.
compress in a vice.
work quickly

ditto what seattle said plus I took a little teeny screwdriver almost like a dental tool and gently pried the 'lips' apart and used the tool to ease the oiled/squashed felt into between the lips and then took a small drift and gently pushed the lips back together again

Firstly, thank you all – great information – and very quickly.

I think I have a plan –

Oil felt seal, compress between wood plates and clamp - let set 8 to 12 hours. With dental probes (I have), gently pry-apart and wedge seal area on assembly to provide additional axial clearance to insert compressed seal. Install seal by working with small screw driver and probes. If successful, selectively peen plates to approximate original axial dimension.

If that does not work I will revert to removing current plates. I have a pair of new plate and will align and drill to accept small machine screws and use thin smear of epoxy to secure assembly.

BTW – I have some Loctite specifically used for sealing hydraulic threads so will use on the three fixing screws for the primary to crankcase attach – great suggestion. When I replaced gearbox seal I re-torqued to 50 ft-lbs with Loctite.

Again – thanks all and stay safe.

Myron your plan is a goot one

Use an O ring instead

@Jdub Put the oil soaked seal in a plastic baggie before compressing. I had no issues doing it like this.